Influence de la vitesse de chauflage sur l'atomisation électrothermique en spectrométrie d'absorption atomique. Applications aux éléments volatils, cadmium et plomb

The advantages of electrothermal atomization by rapid heating (faster than 2000°C s⁻¹) in atomic absorption for the determination of volatile elements are studied. The aim is to control the matrix effects, particularly the very high non-specific absorptions. It is shown that, unlike normal heating, now rapid heating makes it possible to atomize a volatile element without hardly covolatilizing its matrix, as a result of the change in the optimum atomization temperatures.Application examples are given: direct determination of cadmium and lead (atomized respectively at only 900 and 960°C) in sea water and related products. This method is likely to be applicable to other matrices which covolatilize normally with other elements. The mechanisms of atom formation in rapid heating are also investigated.